It is known to provide identification devices that may be applied to articles, such as barcodes and radio frequency identification (RFID) tags that may be read by a suitable reader in order to identify the object to which the device has been applied. In both cases the presence of the device is typically readily apparent to a user by visual inspection due to it's size.
It is desirable to provide a covert identification device the presence of which is not obvious to a user. Furthermore, it is desirable to provide a device which may be detected in a relatively rapid manner at a point of sale of an object, such as, but not exclusively in a retail establishment, so that articles of a particular commercial origin may be distinguished from articles that are not of the same commercial origin, for example counterfeit objects.
It is an aim of embodiments of the present invention to address one or more disadvantages associated with the prior art.